Floating tank roof seal



Sept. 21, 1943. J. H. wlGGlNs FLOATING TANK ROOF SEAL original Filed May 24, 1940 INVENTOR JOHN H. W/GGIMS Mz/M ATTORNEY Patented Sept. 21, 1943 FLOATING TANK ROOF vSEAL lJohn H. Wiggins, Chicago, Ill.

Original application May 24, 1940, Serial No.

Divided and this application February 24, 1941, Serial No. 380,326

1 Claim.

This invention relates to floating tank roof seals of the general type that comprise an annular side wall shoe carried by the floating roof and arranged in sliding engagement with the wall of the tank, and a primary seal, usually constructed from gas-tight fabric, attached to said side wall shoe and to the peripheral portion of the roof, my present application being a division of my pending application Serial No. 337,021, led May 24, 1940.

The primary object of my present invention 1s to provide an eficient means of inexpensive construction, for connecting the primary seal in a gas-tight manner to the floating roof. Other objects or desirable features of my invention will be hereinafter pointed out.

Figure 1 of the drawing is a fragmentary top plan view of a tank roof seal embodying my present invention.

Figure 2 is a vertical sectional view, taken on the line 2-2 of Figure l; and

Figure 3 is a detail sectional view, illustrating the clamping means used to attach the primary seal to the floating roof, and showing the opposed elements of said clamping means spaced a art.

pIn the accompanying drawing, which illustrates my invention, I designates a tank side wall of circular form, 2 designates a floating roof of the pontoon type, pan type, or any other type, arranged inside of said tank, so as to float on the liquid in the tank. A designates a side wall shoe arranged vertically in sliding engagement with the tank side wall, B designates a primary seal usually formed from gas-tight fabric attached to the shoe A and to the peripheral portion of the fioating roof 2, so as to form a closure for the annular space between said roof and the side wall shoe, C designates a secondary seal or auxiliary seal usually formed of fabric arranged adjacent the top edge of the shoe A and adapted to press against the tank side wall I, so as to seal the joint or space between said wall and the shoe, D designates the swinging hangers on the roof 2 arranged so that rollers or friction-reducing devices 3 at the upper ends of said hangers bear against the inner face of the tank side wall, 4 designates vertically-adjustable rods or links suspended from the upper ends of the hangers D and attached to the inner side of the shoe A, so as to suspend said shoe from the hangers in such a way as to insure proper co-operation or coaction of the shoe A with the side wall I of the tank, and 3a in Figure 2 designates compression springs that push the hangers outwardly.

The bottom edge or inner edge of the primary seal B is secured to the oating roof 2 by a novel method that is characterized by arranging said lprimary seal between opposed clamping members 5 on the floating roof, and retaining devices for said clamping members, then manipulating one or both of said clamping members in such a way as to cause a plastic or semi-plastic substance, such as cement, to form a gas-tight, plastic seal between the roof 2 and the bottom edge of said primary seal B. Said opposed clamping members w1ll usually comprise an annular-shaped member x2li rigidly attached to the oating roof 2, and' formed from a fiat, vertically-disposed ring, or from the upright leg of a stationary angle* shaped member on the roof, and a co-acting movable clamping member 25, formed preferably by a plurality of segmental-shaped members that are adapted to be drawn towards the stationary clamping member 24 by tightening the nuts on bolts 26 that pass horizontally through the members 24 and 25. When the clamping members 24 and 25'are arranged in spaced relationship, they co-act with the roof 2 to form a trough that is adapted to receive a quantity of cement 21, or other suitable plastic or semi-plastic material. To clamp the primary seal to the roof the bottom edge portion of said seal is positioned between the memso bers 24 and 25 at a poi/nt above the bolts 2s,

and thereafter the nuts on said bolts are tightened so as to draw the movable clamping members 25 towards the stationary clamping member 24. This operation virtually pumps the cement 35 2l upwardly into engagement with the bottom edge of the primary seal and into the joints between the clamping members 24 and 25 and the primary seal, and forces the cement into all crevices or joints in the clamping means on the roof or in the bottom edge portion of the primary seal B that is embraced by said clamping means, thus producing a plastic seal between the roof and the bottom edge of the primary seal. Moreover, the act of tightening the clamping members 25 tends to smooth out any wrinkles that may exist in the lower edge portion of the primary seal and so thoroughly coat the fabric which constitutes the primary seal B, that there is an absolutely gas-tight joint between said fabric, the top surface of the oating roof, and the parts on the roof that grip said fabric. Figure 2 of the drawing illustrates the fabric clamping means on the roof after the movable clamping members 25 have been tightened. It will 55 be observed that my improved method does not contemplate the use of bolts or similar retaining or fastening devices that pass through the fabric from which the primary seal is constructed. Instead. the bottom edge of the primary seal is arranged above the bolts 26 of the fabric clamping means on the roof.

In order to insure the primary seal B remaining in the position it is intended to occupy and prevent said primary seal from assuming the form of a loop or pocket having an open end disposed so as to catch rain water or dirt, I support the fabric constituting the primary seal, in such a way that relative movement between the roof and the tank side wall, during the rise and fall of the roof, causes said fabric to fold or double upon itself, as shown in Figure 2, without, however, producing a pocket or loop open at its upper end. During the operation of attaching the primary seal B to the roof, as explained above, I install a supporting means G that projects outwardly and upwardly from the outer edge of the iioating roof, and which is of such construction and arrangement that it will not interfere with the movement of the roof inwardly and outwardly towards and away from the side wall of the tank. Preferably, the support G is composed of a plurality of relatively thin or light-weight metal plates with small gaps between their ends, as shown in Figure 2, arranged around the entire circumference of the roof, and provided with downwardly bent portions 28, as shown in Figure 3, positioned inside of the trough-like structure formed by the opposed members 24 and 25 on the roof that reeeive and embrace the bottom edge portion of the primary seal B. Said plates are installed by positioning the bent lower end portions 28 of same between the members '24 and 25 before the nuts on the bolts 26 are tightened, with the result that when the clamping members 25 are moved towards the stationary clamping member 24, the cement 2l will be spread on or distributed over the surface of said plates positioned between the clamping members 24 and 25. 'Ihe plates from which the supporting means G is formed do not have to be shaped or bent to conform to the curvature of the clamping member 24, because said plates are sufllciently thin and short to take the curvature of the stationary clamping member 24 when the movable clamping members 25 are tightened.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

The combination of a gas-tight fabric element, a part to which said element is detachably connected, provided with opposed clamping members, disposed so as to co-act with said part to form an annular trough in which an imperforate portion at the bottom edge of said fabric element is positioned, adjusting devices for causing said clamping members to tightly grip said fabric element, a plastic or semi-plastic sealing substance in said trough that produces gas-tight joints between said clamping members and fabric element and between the edge of said element and the bottom of the trough, and supporting plates for the fabric element positioned between the same and one of said clamping members and projecting upwardly beyond the top edge of said clamping member.

JOHN H. WIGGINS. 

